title: Quantification of mesenchymal stem cell growth rates through secretory and excretory biomolecules in conditioned media via Fresnel reflection.
abstract: An efficient and low cost optical method for directly measuring the concentration of homogenous biological solutes is proposed and demonstrated. The proposed system operates by Fresnel reflection, with a flat-cleaved single-mode fiber serving as the sensor probe. A laser provides a 12.9 dBm sensor signal at 1,550 nm, while a computer-controlled optical power meter measures the power of the signal returned by the probe. Three different mesenchymal stem cell (MSC) lines were obtained, sub-cultured and trypsinized daily over 9 days. Counts were measured using a haemocytometer and the conditioned media (CM) was collected daily and stored at -80 °C. MSCs release excretory biomolecules proportional to their growth rate into the CM, which changes the refractive index of the latter. The sensor is capable of detecting changes in the number of stem cells via correlation to the change in the refractive index of the CM, with the measured power loss decreasing approximately 0.4 dB in the CM sample per average 1,000 cells in the MSC subculture. The proposed system is highly cost-effective, simple to deploy, operate, and maintain, is non-destructive, and allows reliable real-time measurement of various stem cell proliferation parameters.
authors.affiliation: Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia. kavintheran@gmail.com.
authors.forename: Harith
authors.initials: H
authors.lastname: Ahmad
authors.forename: Kavintheran
authors.initials: K
authors.lastname: Thambiratnam
authors.forename: Ahmad Z
authors.initials: AZ
authors.lastname: Zulkifli
authors.forename: Anthony
authors.initials: A
authors.lastname: Lawrence
authors.forename: Ali A
authors.initials: AA
authors.lastname: Jasim
authors.forename: Wijenthiran
authors.initials: W
authors.lastname: Kunasekaran
authors.forename: Sabri
authors.initials: S
authors.lastname: Musa
authors.forename: Nareshwaran
authors.initials: N
authors.lastname: Gnanasegaran
authors.forename: Punitha
authors.initials: P
authors.lastname: Vasanthan
authors.forename: Pukana
authors.initials: P
authors.lastname: Jayaraman
authors.forename: Noor H A
authors.initials: NH
authors.lastname: Kasim
authors.forename: Vijayendran
authors.initials: V
authors.lastname: Govindasamy
authors.forename: Mohammad S
authors.initials: MS
authors.lastname: Shahrir
authors.forename: Sulaiman W
authors.initials: SW
authors.lastname: Harun
mesh_terms: D001704:Biopolymers / Q000032:analysis* / Q000096:biosynthesis*; D015374:Biosensing Techniques / Q000295:instrumentation; D049109:Cell Proliferation; D002478:Cells, Cultured; D003470:Culture Media / Q000032:analysis* / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005434:Flow Cytometry / Q000295:instrumentation; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000502:physiology*; D010783:Photometry / Q000295:instrumentation*; D012031:Refractometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D001704:Biopolymers; D003470:Culture Media